/*
 * Copyright (c) 2007, 2015, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */
/*
 * Copyright 1999-2004 The Apache Software Foundation.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
// $Id: XPathFactoryImpl.java,v 1.2 2005/08/16 22:41:13 jeffsuttor Exp $

package com.sun.org.apache.xpath.internal.jaxp;

import com.sun.org.apache.xalan.internal.XalanConstants;
import com.sun.org.apache.xpath.internal.res.XPATHErrorResources;
import com.sun.org.apache.xalan.internal.res.XSLMessages;
import com.sun.org.apache.xalan.internal.utils.FeatureManager;
import com.sun.org.apache.xalan.internal.utils.FeaturePropertyBase;

import javax.xml.XMLConstants;
import javax.xml.xpath.XPathFactory;
import javax.xml.xpath.XPathFactoryConfigurationException;
import javax.xml.xpath.XPathFunctionResolver;
import javax.xml.xpath.XPathVariableResolver;

/**
 * The XPathFactory builds XPaths.
 *
 * @author Ramesh Mandava
 * @version $Revision: 1.11 $
 */
public class XPathFactoryImpl extends XPathFactory {

  /**
   * <p>Name of class as a constant to use for debugging.</p>
   */
  private static final String CLASS_NAME = "XPathFactoryImpl";

  /**
   * <p>XPathFunctionResolver for this XPathFactory and created XPaths.</p>
   */
  private XPathFunctionResolver xPathFunctionResolver = null;

  /**
   * <p>XPathVariableResolver for this XPathFactory and created XPaths</p>
   */
  private XPathVariableResolver xPathVariableResolver = null;

  /**
   * <p>State of secure processing feature.</p>
   */
  private boolean _isNotSecureProcessing = true;
  /**
   * <p>State of secure mode.</p>
   */
  private boolean _isSecureMode = false;
  /**
   * javax.xml.xpath.XPathFactory implementation.
   */

  private boolean _useServicesMechanism = true;

  private final FeatureManager _featureManager;

  public XPathFactoryImpl() {
    this(true);
  }

  public static XPathFactory newXPathFactoryNoServiceLoader() {
    return new XPathFactoryImpl(false);
  }

  public XPathFactoryImpl(boolean useServicesMechanism) {
    _featureManager = new FeatureManager();
    if (System.getSecurityManager() != null) {
      _isSecureMode = true;
      _isNotSecureProcessing = false;
      _featureManager.setValue(FeatureManager.Feature.ORACLE_ENABLE_EXTENSION_FUNCTION,
          FeaturePropertyBase.State.FSP, XalanConstants.FEATURE_FALSE);
    }
    this._useServicesMechanism = useServicesMechanism;
  }

  /**
   * <p>Is specified object model supported by this
   * <code>XPathFactory</code>?</p>
   *
   * @param objectModel Specifies the object model which the returned <code>XPathFactory</code> will
   * understand.
   * @return <code>true</code> if <code>XPathFactory</code> supports <code>objectModel</code>, else
   * <code>false</code>.
   * @throws NullPointerException If <code>objectModel</code> is <code>null</code>.
   * @throws IllegalArgumentException If <code>objectModel.length() == 0</code>.
   */
  public boolean isObjectModelSupported(String objectModel) {

    if (objectModel == null) {
      String fmsg = XSLMessages.createXPATHMessage(
          XPATHErrorResources.ER_OBJECT_MODEL_NULL,
          new Object[]{this.getClass().getName()});

      throw new NullPointerException(fmsg);
    }

    if (objectModel.length() == 0) {
      String fmsg = XSLMessages.createXPATHMessage(
          XPATHErrorResources.ER_OBJECT_MODEL_EMPTY,
          new Object[]{this.getClass().getName()});
      throw new IllegalArgumentException(fmsg);
    }

    // know how to support default object model, W3C DOM
    if (objectModel.equals(XPathFactory.DEFAULT_OBJECT_MODEL_URI)) {
      return true;
    }

    // don't know how to support anything else
    return false;
  }

  /**
   * <p>Returns a new <code>XPath</code> object using the underlying
   * object model determined when the factory was instantiated.</p>
   *
   * @return New <code>XPath</code>
   */
  public javax.xml.xpath.XPath newXPath() {
    return new com.sun.org.apache.xpath.internal.jaxp.XPathImpl(
        xPathVariableResolver, xPathFunctionResolver,
        !_isNotSecureProcessing, _useServicesMechanism,
        _featureManager);
  }

  /**
   * <p>Set a feature for this <code>XPathFactory</code> and
   * <code>XPath</code>s created by this factory.</p>
   *
   * <p>
   * Feature names are fully qualified {@link java.net.URI}s.
   * Implementations may define their own features.
   * An {@link XPathFactoryConfigurationException} is thrown if this
   * <code>XPathFactory</code> or the <code>XPath</code>s
   * it creates cannot support the feature.
   * It is possible for an <code>XPathFactory</code> to expose a feature
   * value but be unable to change its state.
   * </p>
   *
   * <p>See {@link javax.xml.xpath.XPathFactory} for full documentation
   * of specific features.</p>
   *
   * @param name Feature name.
   * @param value Is feature state <code>true</code> or <code>false</code>.
   * @throws XPathFactoryConfigurationException if this <code>XPathFactory</code> or the
   * <code>XPath</code>s it creates cannot support this feature.
   * @throws NullPointerException if <code>name</code> is <code>null</code>.
   */
  public void setFeature(String name, boolean value)
      throws XPathFactoryConfigurationException {

    // feature name cannot be null
    if (name == null) {
      String fmsg = XSLMessages.createXPATHMessage(
          XPATHErrorResources.ER_FEATURE_NAME_NULL,
          new Object[]{CLASS_NAME, new Boolean(value)});
      throw new NullPointerException(fmsg);
    }

    // secure processing?
    if (name.equals(XMLConstants.FEATURE_SECURE_PROCESSING)) {
      if ((_isSecureMode) && (!value)) {
        String fmsg = XSLMessages.createXPATHMessage(
            XPATHErrorResources.ER_SECUREPROCESSING_FEATURE,
            new Object[]{name, CLASS_NAME, new Boolean(value)});
        throw new XPathFactoryConfigurationException(fmsg);
      }

      _isNotSecureProcessing = !value;
      if (value && _featureManager != null) {
        _featureManager.setValue(FeatureManager.Feature.ORACLE_ENABLE_EXTENSION_FUNCTION,
            FeaturePropertyBase.State.FSP, XalanConstants.FEATURE_FALSE);
      }

      // all done processing feature
      return;
    }
    if (name.equals(XalanConstants.ORACLE_FEATURE_SERVICE_MECHANISM)) {
      //in secure mode, let _useServicesMechanism be determined by the constructor
      if (!_isSecureMode) {
        _useServicesMechanism = value;
      }
      return;
    }

    if (_featureManager != null &&
        _featureManager.setValue(name, FeaturePropertyBase.State.APIPROPERTY, value)) {
      return;
    }

    // unknown feature
    String fmsg = XSLMessages.createXPATHMessage(
        XPATHErrorResources.ER_FEATURE_UNKNOWN,
        new Object[]{name, CLASS_NAME, new Boolean(value)});
    throw new XPathFactoryConfigurationException(fmsg);
  }

  /**
   * <p>Get the state of the named feature.</p>
   *
   * <p>
   * Feature names are fully qualified {@link java.net.URI}s.
   * Implementations may define their own features.
   * An {@link XPathFactoryConfigurationException} is thrown if this
   * <code>XPathFactory</code> or the <code>XPath</code>s
   * it creates cannot support the feature.
   * It is possible for an <code>XPathFactory</code> to expose a feature
   * value but be unable to change its state.
   * </p>
   *
   * @param name Feature name.
   * @return State of the named feature.
   * @throws XPathFactoryConfigurationException if this <code>XPathFactory</code> or the
   * <code>XPath</code>s it creates cannot support this feature.
   * @throws NullPointerException if <code>name</code> is <code>null</code>.
   */
  public boolean getFeature(String name)
      throws XPathFactoryConfigurationException {

    // feature name cannot be null
    if (name == null) {
      String fmsg = XSLMessages.createXPATHMessage(
          XPATHErrorResources.ER_GETTING_NULL_FEATURE,
          new Object[]{CLASS_NAME});
      throw new NullPointerException(fmsg);
    }

    // secure processing?
    if (name.equals(XMLConstants.FEATURE_SECURE_PROCESSING)) {
      return !_isNotSecureProcessing;
    }
    if (name.equals(XalanConstants.ORACLE_FEATURE_SERVICE_MECHANISM)) {
      return _useServicesMechanism;
    }

    /** Check to see if the property is managed by the security manager **/
    String propertyValue = (_featureManager != null) ?
        _featureManager.getValueAsString(name) : null;
    if (propertyValue != null) {
      return _featureManager.isFeatureEnabled(name);
    }

    // unknown feature
    String fmsg = XSLMessages.createXPATHMessage(
        XPATHErrorResources.ER_GETTING_UNKNOWN_FEATURE,
        new Object[]{name, CLASS_NAME});

    throw new XPathFactoryConfigurationException(fmsg);
  }

  /**
   * <p>Establish a default function resolver.</p>
   *
   * <p>Any <code>XPath</code> objects constructed from this factory will use
   * the specified resolver by default.</p>
   *
   * <p>A <code>NullPointerException</code> is thrown if
   * <code>resolver</code> is <code>null</code>.</p>
   *
   * @param resolver XPath function resolver.
   * @throws NullPointerException If <code>resolver</code> is <code>null</code>.
   */
  public void setXPathFunctionResolver(XPathFunctionResolver resolver) {

    // resolver cannot be null
    if (resolver == null) {
      String fmsg = XSLMessages.createXPATHMessage(
          XPATHErrorResources.ER_NULL_XPATH_FUNCTION_RESOLVER,
          new Object[]{CLASS_NAME});
      throw new NullPointerException(fmsg);
    }

    xPathFunctionResolver = resolver;
  }

  /**
   * <p>Establish a default variable resolver.</p>
   *
   * <p>Any <code>XPath</code> objects constructed from this factory will use the specified resolver
   * by default.</p>
   *
   * <p>A <code>NullPointerException</code> is thrown if <code>resolver</code> is
   * <code>null</code>.</p>
   *
   * @param resolver Variable resolver.
   * @throws NullPointerException If <code>resolver</code> is <code>null</code>.
   */
  public void setXPathVariableResolver(XPathVariableResolver resolver) {

    // resolver cannot be null
    if (resolver == null) {
      String fmsg = XSLMessages.createXPATHMessage(
          XPATHErrorResources.ER_NULL_XPATH_VARIABLE_RESOLVER,
          new Object[]{CLASS_NAME});
      throw new NullPointerException(fmsg);
    }

    xPathVariableResolver = resolver;
  }
}
